When coupling, make sure you couple matching glad hands. They are often color-coded to help drivers avoid mistakes. Typically, blue is used for service lines and red is used for emergency lines.

If you are driving a vehicle that is transporting Class 1 explosives and it is involved in an accident, you should warn others of the danger, keep bystanders away, and not allow smoking or open fires near the vehicle. Before separating the vehicles involved in the collision, remove all explosives and place them at least 200 feet away from the vehicles and any occupied buildings.

The average driver has a reaction time of between three-quarters of a second and one second.

Low beam headlights allow you to see about 250 feet ahead of your vehicle. When driving at night, adjust your speed so that you will be able to stop in the distance illuminated by your headlights.

A material's ID number must appear on its accompanying shipping paper as well as on its packaging. It must also appear on cargo tanks and other bulk packaging.

On combination vehicles with air brakes, the tractor protection valve keeps air in the tractor or truck brake system, should the trailer develop a bad leak or break away from the tractor.

Hazardous materials placards must be positioned so any words or numbers can be read from left to right. They must be at least three inches away from any other markings.

The service air line carries air and is controlled by either the foot brake or trailer hand brake. The service air line is attached to relay valves, which allow the trailer brakes to be applied quickly.

All commercial motor vehicles are required to be equipped with the proper emergency equipment. This may include spare electrical fuses; three red reflective triangles, six fuses, or three liquid burning flares; and at least one properly charged and rated fire extinguisher.

If a trailer is attached to a tractor, the adjustment of the vehicle's mirrors can only be checked accurately if the trailer is straight.

If the weight of your vehicle prevents you from matching the speed of surrounding traffic, you should stay in the right lane, if possible.

Unbaffled tanks are also often referred to as "smooth bore tanks."

Factors that can affect your vehicle's stopping distance include driving speed, the vehicle's weight, and the slipperiness of the road surface.

If you stay in neutral for too long while double clutching and have difficulty switching your vehicle into the next gear, don't force it. Return to neutral, release the clutch, increase the engine speed to match road speed, and try again.

When passing a bicycle, you must allow at least four feet of space between the bicycle and your vehicle. If necessary, and if you can do so safely, you are permitted to cross the double yellow centerline so you can maintain the four feet of clearance between your vehicle and the bicycle.

Correctly following the steps to couple and uncouple trailers is vital to safely operating a combination vehicle. After connecting the air lines to the trailer while coupling, you should supply air to the trailer.

Be cautious when driving near people who are not paying attention to the road. Be wary of road workers, drivers who are engaged in conversation with passengers, and children near the road.

Before inspecting the engine compartment, make sure that the parking brakes are on and/or the wheels are chocked. Check the engine compartment before entering the cab and starting the engine.

The controlled braking method for emergency stops involves applying the brakes as hard as you can without locking the wheels. Keep steering wheel movements small when braking in this way.

When driving through work zones, you should make a particular point of reducing your speed when workers are on or near the road.